Sewing-machine.



F. BAKER.

SEWING MACHiN E. APPLICATION FILED :uuEzo. 19'13.

Patented gept. 4, 1917.

. mww c 4 SHEETS-SHEET1.

F. BAKER.

SEWING MACHINE. APPLICATION FILED JUNE 20 1913.

Patented Sept. 4, 1917.

4 SHEETS-SHEET 2.

F. BAKER.

SEWING MACHINE.

APPLICATION FILED JUNE 20. I9I3- L QWQWQ Patented Sept. 4,1917.

4 SHEETSSHEET 3.

F. BAKER.

4 SEWING MACHINE. eucmou FILED JUNE 20. 1913.

Patented Sept. 4,1917.

4 SHEETS-SHEET 4 inn smarts PATENT rrion.

FREDERICK BAKER, OF BLAflKHEATl-I, ENGLAND, A$SIGNOR IO BAKER SEWING.MAOHINE TRUST, LIMITED, OF LONDON, ENGLAND.

SEWING-MACHINE.

Application filed June 20, 1913.

To all whom it may concern:

Be it known that I, FREDERICK BAKER, a subject of the King of GreatBritain, residing at 42 Lee road, Blackheath, in the county of Kent,England, have invented certain new and useful Improvements in andRelating to Sewing-Machines, of which the following is a specification.

This invention relates to sewing machines and has particularreference'to machines of the kind in which an angularly movable loopdrawing device situated below the needle plate engages the needle threadat each descent of the needle and after pulling out a loop of threadbecomes disengaged from the same before the bight has been carriedthrough a semi circle. A machine working on this principle of earlyrelease of the loops is provided with a stationary casing, which issituated adjacent to the loop drawing device and contains a looparresting and retaining element in the case of producing single threadstitching, as disclosed in United States Patents No. 1014033 and No.1072201, or a spool of thread in the case of producing double-threadlock stitching, as disclosed in United States Patent 10%7 728. In thecase of producing single-thread lock stitching the casing and its looparresting and retaining element may be termed a tension device since itarrests certain loops and yielclingly retains them in tension whileothers are allowed to pass freely over the device.

One of the objects of the present inven tion is to provide a form oftension device of greater precision and certainty of action than thetype of device hitherto employed, and in particular to provide for arotary motion of the loop arresting and retaining hook, or to so modifythis element that it cannot catch any loop except that which it isintended to catch and ultimately enables the bight of a rightly caughtloop to become disengaged without necessitating an actual unhookingaction. A further object is to alter the position of the stationarycasing, so as to improve the manner in which the loops are made to passaround and over it, and reduce the extent of the movements required inmanipulating the loops generally. Improvements in these and otherdirections as hereinafter eX- plained result in simplification of parts,in)

Specification of Letters Patent.

Patented Sept. at, 191?.

Serial No. 774,801. a

proved timing and adjustment, and a su invention the looparresting andretaining element of the tension device for single threadstitchingperforms its functions by a rotary motion. A convenient form of the saidelement comprises a circular plate rotatably mounted within the casingof the device, and a number of hooks or equivalent loop arrestingelements formed or carried on or near the periphery of the plate, ashereinafter more fully explained.

In a modified form of the tension device the loop arresting andretaining element, after arresting a loop, loses its loop-arrestingproperty but preserves its loop-retaining property until it has movedinto its loop-delivering position, whereupon it also loses itsloop-retaining property. A convenient form of loop arresting andretaining element of this kind is one of an oscillatory charactercomprising two members one of which serves, at the correct intervals, toshroud the other member so as to render it incapable of wrongly catchinga loop and also serves to retain a rightly caught loop and prevent itfrom escaping prematurely. The one member closes upon the other,preventing premature escape of an arrested loop and shrouding the looparresting member, and subsequently the members open, there by freelyreleasing the loop.

The above mentioned stationary casing either contains a spool or bobbin,or a loop arresting and retaining element, as hereinbefore stated. Ineither case it has been found advantageous to locate the said stationarycasing laterally with respect to one face of the loop drawing disk. Thesaid casing may be kept in contact with the loop drawing disk byintermittently retracted prongs, or by a roller, or by a laterallyprojecting member on a rotating plate engaging in a corresponding grooveon the rear face of the casing, as hereinafter described. Theintermittent retraction of the prongs or the speed of rotation of theplate is suchthat the passage of the thread over the corresponding faceof the stationary casing is nothindered and may in fact be assisted.

The above stated lateral positioning of the stationary casing enables anew principle ofmanipulation of the thread to be adopted as will now beexplained. It will be understood that in this case the needle at eachdescent passes down between or alongside the sliding surfaces of thestationary casing and the loop-drawing disk; means are thereforeprovided whereby each loop of thread formed at the commencement of eachascent of the needle is turned over by the engaging of its bulgingstrand and the drawing-out of it across the inner face of the casing,whereupon it becomes free to be drawn up over the outer face of thecasing, a part of the loop having meanwhile been slidably detained nearthe path of the needle. In order that the loops of thread may be drawnout in this way, one or more loop engaging elements projecting from theface ofthe disk may be provided, a recess or number of recesses in theadjacent face of the-casing be ing formed to permit these elements-topass within and along the same. A convenient form ofprojecting element,and one which also assists in keeping the casing in its correct positionagainstthe face of the disk, is a laterally projecting tongue with a.gap in it, the part with which the'tongue engages on the adjacent faceof the casing comprising an arc-shaped groove. In this way the casingmay be kept quite near to the rear face of the disk, the said tonguesliding in the groove as the disk rotates. The disk and easing are sosituated relatively to the needle that as the latter descends it passesdown near the face of the disk. In order that the needle may makethisdescent and form a loop, a portion of the tongue is cut away and aportion of the disk may be cut away as well; the timing of the parts isof course such that the gap in the circular tongue registers with thepath of the needle at the time when the needle is in the act of and isthen in such a position that, when it is being drawn up, one strand ofthe loop will glide over the outer face of the casing.

In order that the invention'may be clearly understood and readilycarried into effect the same will now be described more fully withreference to the accompanying drawings in which Figures 1 to 1illustrate diagrammatically the :new. principle of drawing out loops ofthread as hereinbefore mentioned; Figs. 1

and 2 show a tension device situated later,- ally with respect to theloop drawing disk (shown in dot and dash lines) and two positions of aloop in the course of-encircling the device; Figs. 3 and 1 show thedevice enlarged and the thread in two other positions. I r 1 i Fig. 5 isa longitudinal sectional elevation, Fig. 6 an end elevation, and Fig. 7a plan, of parts of a machine operating on the new principle referredto. It will be understood that Fig. 6 is an elevation asviewed from.thefront end of the machine, that is to say as viewed from the right handend of Fig. 5.

Fig. 8 is a view of the rear face of the loop'drawing disk and Fig.9co1'responds with Fig.36 with the exception that the disk is removed.

Fig. 10 is a detail view of part of the mechanism shown in Figs; 5, 7and 9. 1

Figs. 11 to 17 relate to the construction of the tension device usedwith the disk and other machine parts shown in Figs. 5 to 10. Thistension device presents slight modifications as compared with .thatshown in Figs. 3 and 1.

Fig. 18 shows d1agrammat1cally the function of a lip on the disk forcontrolling the position-of the strand of a loop when being drawn out,as hereinafter described.

Fig. 19 is a side elevation and Fig. 20 an end view of parts of amodified machine in which the conveying of the loops past the outer faceof the tension device, and the keeping ofthe latter in position, areperformed by a continuously rotating plate; Fig. 21 is a view of theback face of the loop drawing disk; Figs. 22 and 23 show in endelevation and in two different positions the driving mechanism for thedisk and plate, and Fig. 24- is a side elevation corresponding to Fig.23; Fig. 25 is a viewof the outer face-of the tension device by itself.

Figs. 26 and 26 illustrate one form of intermittently actuated prongmechanism to keep the tensiondevice in its lateral posi tion against theloop-drawing disk.

Figs. 27, 27 27*, 27 and 2S, illustrate the internal mechanism of atension device of the finger-shrouded type hereinbefore re tensiondevice of Fig. 27. Fig.29 is similar to Fig. 29 but the loop drawing.disk is removed, exposing the tension device and other parts behind it.7 I

Figs. 30, 31 and 32- i llustrate a modified form of .the finger-shroudedtype of tension device, Fig. 30 being .anexternal view, and Figs. 31 and,32 two .internal views.

Referring now to the diagrammatic Figs. 1 to a, and the correspondingmachine parts shown in Figs. 5 to 10, it may be noted in the first placethat therotary diskB rotates counter clockwise as viewed from the frontend of the machine. Viewing the parts from the front end of the machine,the vertical diameter of the loop arresting plate (Z Within the casing Dof the tension device appears in the same vertical line as the path ofthe needle; the part of the casing on the right hand of the path of theneedle is approximately semi-cylindrical and the remaining part and alsoincluding its tail portion extends downwardly toward the left, the tipof the tail being practically on the 'path of a circular tongue B with agap in it, the tongue being formed laterally on the disk and sliding ina groove in the tension device casing. The needle descends in a cutawayportion D (Fig. 7) of the casing against the vertical diameter of theloop arresting plate and between it and the gap in the tongue B on thedisk, and the groove D in the casing extends from a point just to theleft of the needle to the tip of the tail portion. When the needle A isdown and presenting a loop of the thread C. The advancing end of thetongue B on the disk catches the bulging strand and immediatelyafterward enters the groove D in the casing, the result being that thestrand becomes trapped and drawn along across the inner face of thecasing as shown in Fig. 1, and is unable to escape until the advancingend of the tongue passes out of the groove at the tail of the casing,whereupon the bight of the loop becomes released from the tongue andmoves in a direction away from the disk and toward the outer face of thecasing, as shown in Fig. 2. The size and position of the casing Drelatively to the disk B are preferably such that the bight of each loopof needle thread need not be drawn out through more than about ninetydegrees or at most about one hundred and twenty degrees of angularmovement.

In order to keep one part of the strand of each loop in place while thebulging part is being caught, and drawn across the inner face of thecasing, released, and then drawn back across the outer face of thecasing, a catch D is formed or provided on or near the lower corner ofthe groove D in the casing at the entering end of the groove, the saidcatch being adapted to arrest and retain one part of the loop as shownin Figs. 1 and 2, while the other part is being manipulated asdescribed. After the manipulated part of the loop, in passing backacross the outer face of the casing, has come into vertical alinementwith the retained part, the two parts or strands. constituting the loop,pass up over the semi-cylindrical right hand part of the casing as shownin F 3. In the case of single thread lock-stitching the loop in passingup over the said right hand portion of the casing is arrested or not bya projecting hook (Z on the circular loop arresting plate (Z accordingas a hook is in position (Fig. 3) or not (Fig. i). If a hook is inposition the rear thread of the arrested loop slips over the curved wallof the casing into the space immediately behind the loop arrestingplate, the other strand extending of course immediately across the frontface of the plate as seen in 4:. In this way lock stitching of the kinddisclosed in the specification of the prior United States Patent No.1072201 is produced. If it is desired to produce the type of stitchingin which each sub-loop merely embraces the main loop without be ingembraced by it, each main loop While being retained in tension is socontrolled that the needle in descending for each sub-loop passes downat one side of the retained main loop. If on the other hand it isdesired that each sub-loop should not only embrace the main loop but beembraced by it, the main loop is kept slightly expanded so that theneedle at each descent for the formation of a sub-loop passes throughthe retained main loop.

The bight of every loop that is arrested by one of the hooks is drawntoward the hole in the needle plate by the action of the takeup or ofthe feed mechanism that ad.- vances the material stitch by stitch. Thisforward movement of the loop causes the plate to turn upon its axis andthe retation of the plate ultimately presents the bight quite close upto the hole in the needle plate. Another loop is then drawn from theneedle. and it is necessary for the bight of the old loop to be then setfree. This release of the bight of the old loop may be effectedautomatically by the mere turning effect upon the rotary plate of thenext main loop as the latter is being formed on the next hook, or by thefeed movement. The actual presentation of the bight to the needle at theinstant when the needle deilscends to pierce the bight will be referredto ater.

In. this machine the means for keeping the tension device casing inposition against the face of the disk comprise an oscillatory seg ment Fadapted to work in a depression or track D formed to receive it on therear face of the casing, as shown clearly in Figs. 10 and 17. Thissegment forms part of a sleeve F which is rotatably mounted in a bracketand is also formed with a toothed segment F The plane of the segment Fis at about forty-five degrees to the horizontal, and its periphery hasa small axially disposed groove F cut in it for the purpose hereinafterdescribed. A toothed segment G pivoted to the frame of the machine, orto a bracket thereon, engages with the toothed segment F of the sleeve Fand is intermittently oscillated by the engagement with. a slot 9 (Fig.10) in the said segment of a pin or roller'g carried on one end of a rodG (Figs. 5 and 7) the other end of which carries a roller G working in acam groove G formed in a collar G on the main shaft. The operation ofthese parts is as follows :Vi hen the strand of a loop is being drawn upover the outer or rear face of the tension device casing, the cam grooveG operates the rod G which oscillates the toothed segment G, which inturn oscillates the toothed segment F and thereby causes the segment Fto turn. At the instant when the strand arrives at the position where ithas to pass between the segment F and the outer face of the casing, theaxially disposed groove F in the segment F is in a position to coincidewith the strand, with the result that the strand, instead of beingpinched between the segment and the casing, is housed in the groove Fand is wiped forward by the angular motion of the segment. When thestrand is delivered free on the other side of the track D this segment(F) is returned to its normal position by the retraction of the rod Gdue to the action of the cam groove G Owing to the fact that the outerface of the casing is recessed at D with the segment F working in therecess or track, the tension device is kept in posit-ion against theface of the disk B, but in order that the friction between the disk andthe inner face of the casing may not cause the casing to slip angularly,a stop may be provided to butt up against the tail portion of thecasing. Such a stop is shown in Figs. 5 and 7, it being constituted byone wing II of a two winged sleeve H, the other wing H of which isattached to one end of a spring H which keeps the wing H normallypressed against the tail end of the tension device casing. The wing H ishowever intermittently tapped in order momentarily to move the wing Haway from the casing at the instant when loops pass over the tail of thecasing. This tapping of the wing is effected by the end of the rod G;the movement required to be imparted to the wing II is much less thanthat performed by the rod Ur and the wing is therefore so placed thatthe rod engages with it only for a fraction of the total movement of therod.

In order that the strand of a loop when being drawn out may not slipbetween the tension device casing and the disk, the loop is expanded byproviding on the disk a lateral'circular lip B at its periphery. Thislip, which extends around the greater portion of the periphery as seenclearly in Fig. 8, rides upon a curved ledge 13 (Fig. 13) on theadjacent face of the tension device casing and the strand necessarilypasses from the bight up through the gap in the disk (Fig. 18) and lieson the outer curved surface of the lip or of the casing, which twosurfaces act as though they were one unbroken surface.

In case the bight of a loop, when released, should adhere to the disk, awiper in the form of a segmental strip of metal K, shown in Fig. 9, iscarried by a bracket K and is situated to lie in a circular groove Bformed at the base of the channel between the tongue B and lip 13 of thedisk B. This wiper is situated near the tail of the tension devicecasing as shown in Figs.,6 and 9. Fig. 9 also shows clearly a cam K foroperating the feed plate K in a manner well understood. In this figure(Fig. 9) is also seen a guide K" to direct the bight of each main looptoward the point at which the loop arresting plate of the device isexposed.

More specific reference will now be made to the construction of thetension device illustrated as being used with this machine. The devicecomprises the casing proper D and a cover piece screwed thereon. Thesegmental groove D is formed on the face of the cover piece and thecatch D is formed on the lower edge of the groove at its forward end.The external surface of the cover piece on the lower side of the grooveis slightly receding so that the strand of a loop when caught on thecatch D and being drawn out toward the tail of the casing is not nippedbetween the surface of the cover piece and the adjacent surface of thedisk.

To enable the internal mechanism of the device to be placed in positionthe casing is suitably recessed as shown in Fig. 11. The loop arrestingplate- (Z (Fig. 15) has a central hole in it to enable it to fit upon anannular hub (Z (Fig. 11). The locking lever (Z engages with notches clon the loop arresting plate at intervals and is released therefrom bythe engagement of the cam 6P on the disk (Fig. 8) with the nose (Z onthe locking lever. The loop arresting plate is locked during the periodswhen a main loop is caught by a hook on the plate and is being formed onthe hook by the action of the take-up. The plate is then released asabove described and is able to turn stepby-step as the loop is drawnforward stitch by stitch by the feeding mechanism. Suitable means,however, are provided to restrain or control the freedom of the plate inits rotation. Such means may, for instance, consist of a small flatspring cl, housed in the inner face of the cover piece, as shown in Fig.14, and bearing against the adjacent face of the loop arresting plate (Zto exert a restraint upon the movements of the plate. Each hook on theplate is presented at one period in the path of the loops and afterwardbecomes housed under the curved wall of the casing. as will be readilyunderstood. The bight of each arrested loop is finallv delivered orescapes from the hook. It will casing.

be understood that if the hooks on the arresting plate are actually inthe plane of the plate, as shown in Figs. 12 and 15, they cannot presenta bight centrally to the needle since the latter in its ascent anddescent has to pass at one side of the plate; consequently, means, suchas a horn J, must be provided, in order to keep the loop open andeventually present the bight centrally to the needle so that the lattermay pierce it. The horn J illustrated in Figs. 12 and 13 is formed on asegmental plate J (Fig. 16) having a center pin J 2 whichfits into ahole in a boss (Z projecting centrally within the annular hub (Z of thetension device A small spring coiled within the annular space betweenthe hub d andthe boss ai engages with a stop J on the underside of thesegmental plate J. The coiled spring keeps the horn J and plate J in anormally lowered position, the horn pointing at an angle of aboutthirty-five degrees to the vertical. The edge J of the plate J bearsagainst a ledge J (Fig. 14) on the inner face of the cover piece of thedevice to limit the downward angular movement ofv the born. When a loopis caught by a hook on the loop arresting plate and this plate movesforward angularly, the bight of the loop embraces not only the hook butalso the horn, and when the hook reaches the horn these two parts moveangularly together until the hornis nearly vertical, that is to saynearly in line with the path of the needle. The bight is then in a trulycentral and appropriately expanded condition, so that, when the needledescends, it cannot fail to penetrate the bight. As soon as the bightescapes, the plate J, carrying the horn with it, springs back to itsnormal position.

In contrast with this movable horn, the horn of the device shown inFigs. 3 and 4 is stationary, being integral with the cover piece ofthetension device casing.

A modification of the rotary type of mechanism for keeping the tensiondevice in position and in some respects an improvement upon themechanism described with reference to Figs. 5to 10 is illustrated inFigs. 19 to 24iand will now be described. In this case the function ofthe oscillatory segment of the machine shown in Figs. 5 to 10 isperformed by the plate L mounted in a plane parallel with the plane ofthe loop drawing disk B, and formed with a laterally projecting flange Zadapted to slide in a corresponding segmental groove Z" (Fig. 25) on theouter face of the tension device casing. The flange Z? (which has agapin it) and groove Z serve efficiently to keep the tension device inposition, and the gap between the ends of the flange allows the threadto pass between the plate L and the casing of the device withoutbecoming pinched between them, just as the groove on the segment F ofFig. 10 prevented pinching of the thread. The plate L is mounted upon aspindle L, the rotation of which is properly timed relatively to therotation of the main shaft. The said spindle is conveniently driven fromthe same source of power as that which drives the main shaft; such anarrangement is shown in Figs. 22 to 24: where L represents a crank onthe usual top or power shaft of the machine and L represents a slottedconnecting rod connected at one end with the crank and at the other endwith a short link L pivoted to a driving disk L mounted on the rear endof the main shaft of the machine. A pivoted block L works in the slot inthe connecting rod L and provides the connecting rod with the necessarycenter of oscillation in the known manner. The connecting rod isslightly shorter than the distance between the axes of the top andbottom shafts with the result that the bottom or main'shaft has anaccelerated motion during part of each revolution, as is wellunderstood. An arm L on the connecting rod is pivotally connected to adiametrically mounted bar L slidably dove-tailed onto the face of a diskL which disk is mounted on the rear end of the spindle L, the front endof which carries the flanged plate L. Hence the main shaft and thespindle will be driven together. at substantially the same rate from thetop shaft by a single connecting rod, namely the slotted rod L In thetwo constructions shown in Figs. 1 to 18 and 19 to 25 respectively, thetension device casing is kept in position against the rear face of theloop drawing disk by means of an oscillatory segment, or a flangedrotary plate. The tension device might however be kept in positionotherwise, as for instance by means of prongs intermittently retractedat certain intervals to allow the loops to pass across the rear face ofthe casing. One form of SIICll prong mechanism is illustrated in Figs.26 and 26. A bracket 0 supported by some stationary part of the machinecarries two spring-controlled prongs M and N which are shaped atthefront ends to engage in corresponding recesses in the rear face of thetension device casing D and carry at their rear ends balls h Nrespectively bearing against a plate P having cam shaped recesses m andn on its face in a position such that, as the plate rotates, the ball Mat the rear end of the prong M travels in the recess on, and the ball Nat the rear end of the prong l travels in the recess n. The plate Pnormally keeps the balls M and N and hence also the prongs M and Nthrust toward the rear face of the tension device casing but therecesses m and it allow the controlling springs M N of the prongs toretract the latter at the correct instants to allowthe thread of theloops whenbeing drawn up to pass between the front ends of the prongsand the rear face of the casing.

Reference will now be made to the forms of tension device in which theloop arresting element consists of two members one of which shrouds theother at certain intervals.

In the construction shown in Figs 27, 27 27 and 28 the loop arrestingelement consists of a member Q which is rotatably mounted in acylindrical recess in the tension device casing D and is provided with aloop arresting finger q and a tail piece 9, and a member R which ispivoted at 1" upon the tail piece The member R consists of the tailpiece 1" which approximately coincides in shape with the tail piece g,and the shrouding arm 7 A spring S attached at one end to the casing Dand at the other end to a point on the shrouding arm 9 of the member Rtends to keep the end of the shrouding arm 1 in contact with the end ofthe finger g, and also tends to keep both members in such a positionthat the ends of their tail pieces 9 1" lie in a hole S in the curvedwall of the casing. A lever S" pivoted at s (Fig. 29 to a stationarypart of the machine is connected to or formed integrally with an arm 8'terminating in a pin 8 working in a cam groove 8 on the looping drawingdisk. The other end of the arm S is specially shaped; one half of it-istapered as seen at 8 in Figs. 27 and 27, so that, when the lever S isoscillated by the cam groove 5- and pin 8 this tapered end glides underthe end of the tail piece 9 and holds the member Q, firmly; the otherhalf is wedge-shaped as seen at s in Figs. 27 and 27 so that, when thelever S is oscillated, this wedge-shaped end, in passing under the endof the tail piece 9*, forces this tail piece upward and thereby causesthe end of the shrouding arm 1 to move away from the end of the fingerg. The operation is as follows :Prior to the instant at which a loop ofthread is to be caught by the finger the specially shaped end of thelever S enters the hole S of the casing, and thereby locks the member Qin position and tilts the member R sufficiently to enshroud the fingerThis finger then catches the loop as the latter is being drawn up overthe casing; when the loop has been fully drawn out upon the finger thelever S moves back to its normal position, thereby allowing theshrouding arm 7' to again engage with the end of the finger piece (1.The two members then move forward stitch by stitch in opposition to thetension of the spring S and the loop or loops that are not intended tobe caught by the finger are guided over the end thereof by the shroudingarm W, as will be understood from Fig. 27. When the end of the finger garrives almost vertically under the hole in the needle plate, the tailpiece 9 moves beyond a notch 9 on a pivoted pawl Q3 and is therebyprevented from returning until released, and the tail piece 7'' of themember R projects into a hole S in the casing. A spring controlled cam Spivoted at s on the driving shaft then passes into the hole S in thecasing and engages with the tail piece 1" and thereby tilts the memberR, with the result that the shrouding arm 7 moves away from the fingerpiece q and allows the bight of the retained loop to slip off, and thesaid cam almost immediately afterward engages a toe Q4011 the armthereby thrusting it backward against a controlling spring Q5 andreleasing the tail piece g; The spring S then returns both members totheir lowered position.

Figs. 30, 81 and 82 illustrate a modifiec form of tension device of theshrouded finger type. In this form of the device the finger g isconstituted by an upward and outward projection from a disk 9* rotatablymounted in a cylindrical recess in the tension device casing. The disk gis controlled by an underlying coil spring QXX so as to normally assumethe position shown in Fig. 31. The shrouding arm r is constituted by aprojection on a disk 1" rotatably mounted upon and concentrically withrespect to the disk 9" as' seen in Fig. 32. The disk 7" is controlled byan underlying coil spring 0 which tends to keep the end of the shroudingarm "1' in contact with the finger g in order to shroud the latter asalready described with reference to Figs. 27 and 28. T is a pawl pivotedat t and provided with a locking tooth t for engagement with slots t tin the disk 9*. The tootht of this pawl T is formed with a raisedprojection i having an inclined surface for engagement with a notch t onthe disk 1"". A spring 25 thrusts the pawl T against the disks g", 7,and a tail piece t on the pawl projects-through the casing forengagement withnotches or camshaped projections t t on a rotary hub i Ona pivot t, a pawl T is pivoted, and is formed with a nose t forengagement with a notch 25* on the disk 7" The operation is as follows:the disk QX is normally locked by the tooth t, and the disk 9 isnormally turned backward in opposition to its spring by the thrust ofthe incline on the projection i against the notch 6*, thereby causingthe shrouding arm 7" to be-retra'cted slightly relatively to the fingerA loop is there fore caught and drawn out upon the finger and theprojection on the hub i then engages a tail piece 25 of the pawl T andthereby turns the pawl about its pivot 16 in a clockwise direction tosuch an extent that the tooth t becomes withdrawn from the slot 25thereby allowing the finger to adva-n ce slightly; the same clockwisemotion of the pawl T causes the projectionzf to become withdrawn fromengagement with the notch and thus allows the diskr to turn and placethe shrou'ding arm 7* into its shrouding position relatively to thefinger The disk then yields stitch by stitch and is followed up by thedisk a. When the finger g is in a practically vertical position underthe hole in the needle plate the tooth t on the pawl T engages in theslot t and again locks the disk 9* and a projection t on the hub tthrusts the pawl T slightly upward thus causing the projection t on thispawl to press against the notch on disk 1"" and turn this disk slightlybackward, thereby enabling the bight of the loop on the finger toescape. The cam shaped projection t then engages with the tail piece 23on the pawl T and rocks the same thereby unlockingthe disk 9* whichimmediately flies back to its lowered or normal position, thrusting backthe disk 7 with it.

What I claim and desire to secure by Letters Patent of the United Statesis 1. In a sewing machine, the combination with an angularly movableloop-drawing device operating to draw out successive loops from theneedle thread but allow each loop to be released before its bight hasbeen ,car-

released before its bight has been carried through two right angles ofangular movement, of a stationary tension device laterally situated withrespect to one face of the plane of movement of the loop drawing meansand comprising a casing around and over which the loops pass in beingdrawn up, and means within the casing for temporarily arresting certainloops while allowing others to pass.

3. In a sewing machine, the combination with an angularly movableloop-drawing device, of a tension device comprising a stati onary casinglaterally situated with respect to one face of the loop drawing device,and

cooperating parts upon the adjacent lateral faces of the loop-drawingdevice and the casing adapted to cause the bulging strand of a looppresented by the needle at the commencement of each ascent, to betrapped and the bight of a loop to be drawn out between the saidadjacent lateral faces and released at the tail of the stationary casingin a way that permits of the loop being drawn up around and over thesame.

l. In a sewing machine, the combination of an angularly movable disk, atension device comprising a stationary casing located laterally withrespect to one face of the disk,

and interengaging means adapted to cause the bight of successive loopsto pass between the adjacent lateral faces of the disk and the casingand each loop to be released before its bight has been carried throughtwo right angles of angular movement and in a. position from which whendrawn up it will pass around the casing.

5. In a sewing machine, the combination of an angularly movable disk, astationary casing located laterally with respect to one face of thedisk, and tongue and groove intor-engaging parts on the adjacent facesof the disk and the casing operating to entrap the bulging strandpresented by the needle at the commencement of each ascent and draw outthe bight of loop between the of the casing for cooperation with theloop engaging element to entrap and draw out successive loops betweenthe sliding surfaces of the disk and the casing and to release each loopbefore its bight has been carried through two right angles of angularmove ment, and means for slidably detaining one strand of each loop nearthe path of descent of the needle while the loop is being drawn outbetween the said sliding surfaces.

7. In a sewin machine, the combination of a rotatable disk, a stationarycasing in slidable contact with one face of the disk, a circular tongueon the face of the disk cooperating with an arcuate groove in theadjacent face of the casing to draw out successive loops froin theneedle thread but allow each loop to be released before its bight hasbeen carried through two right angles of angular movement, a part of thetongue being removed to present an abutment to engage the bulging strandof the needle thread as the needle begins to ascend.

8. In a sewing machine, the combination with angnlarly movable means forengaging the needle thread, of a stationary casing laterally situatedwith respect to the plane of movement of the aforesaid means and inslidable contact therewith, the adjacent faces cooperating to draw outsuccessive loops from the needle thread but allow each loop to bereleased before its bight has been carried through two right angles ofangular movement, and means for keeping the stationary casing in itslateral position with respect to the loop-drawing means but perlOOmitting the loops of thread to pass over the casin 9. In a sewingmachine, the combination with angularly movable means for engaging theneedle thread, of a stationary casing latorally situated with respect tothe plane of movement of the aforesaid means and in slidable contacttherewith, the adjacent faces cooperating to draw out successive loopsfrom the needle thread but allow each loop to be released before itsbight has been. carried through two right angles of angular movement,means for retaining the stationary casing in its lateral position withrespec to the loop-drawing means but permitting the loops of thread topass over the casing, and means for operating the said retaining meanssynchronously with the loop-drawing means.

10. In a sewing machine, the combination with an angularly movableloop-drawing device operating to draw out successive loops from theneedle thread but allow each loop to be released before its bight hasbeen carried through two right angles of angular movement, and astationary casing around and over which the loops pass, of a rotatablemember in contact with the casing to keep it in position relatively tothe loop-drawing device.

11. In a sewing machine, the combination with an angularly movableloop-drawing device, of a stationary casing situated laterally withrespect to one face of the loop drawing device, cooperating parts uponthe adjacent faces of the device and the casing to entrap the needlethread and draw out a loop between the adjacent faces before it has beencarried through two right angles of angular movement, an angularlymovable member for retaining the stationary casing in its lateralposition with respect to the loop drawing device, and means foroperating the angularly movable member so that the travel of a gap inits surface synchronizes with the travel of the loops of thread in beingdrawn up around the casing.

12. In a sewing machine, the combination with an angularly movableloop-drawing de vice, of a stationary casing situated laterally withrespect to one face of the loop drawing device, cooperating parts uponthe adjacent faces of the device and the casing to entrap the needlethread and draw outa loop of needle thread between the adjacent facesand deliver the bight of the loop at the tail of the casing before thebight has been carried through two right angles of angular movement, anda rotatory member mounted in contact with the outer face of the casingto keep it in its lateral position relatively to the loop drawingdevice.

13. In a sewing machine, the combination with an angularly movable loopdrawing device, operating to draw out successive loops from the needlethread but allow each loop to be released before its bight has beencarried through two right angles of angular movement, of a stationarycasing laterally situated with respect to one face of the loopdrawingdevice, and an angularly movable loop arresting and retaining element inthe said casin let. In a sewing machine, the combination with anangularly movable loop-drawing device operating to draw out successiveloops from the needle thread but allow each loop to be released beforeits bight has been carried through two right angles of angular movement,of a stationary casing laterally situated with respect to one face ofthe loop drawing device, an angularly movable loop arresting andretaining element in the said casing, and means for exerting a yieldingrestraint to the angular movement of the said element as the sewingadvances.

15. In a sewing machine, the combination with an angularly movable loopdrawing device operating to draw out successive loops from the needlethread but allow each loop to be released before its bight has beencarried through two right angles of angular movement, of a tensiondevice comprising a stationary casing, laterally situated with respectto one face of theloop drawing device, an angularly movable looparresting element within said Casing, means whereby the said element islocked during the arresting of a loop, means whereby it is thenunlocked, and means whereby it then yieldingly retains the loop untilone or more stitches are completed and the bight has been penetrated bythe needle.

16. In a sewing machine, the combination with an angularly movable loopdrawing device, operating to draw out successive loops from the needlethread but allow each loop to be released before its bight has beencarried through two right angles of angu lar movement, of a tensiondevice comprising a stationary casing laterally situated with respect toone face of the loop drawing device, a loop arresting. and retainingelement mounted within the casing, and means operating to temporarilydeprive the loop arresting and retaining element of its loop arrestingproperty after arresting a loop and then to temporarily deprive it ofits loop retaining property also. i

17. In a sewing machine, the combination with an angularly movable loopdrawing device, operating to draw out successive loops from the needlethread but allow each loop to be released before itsbight has beencarried through two right angles of angular movement, of a tensiondevice comprising a stationary casing laterally situated with respect toone face of the loop drawing device,

a loop arresting and retaining element mounted within the casing, andserving to engage, retain, protect and release a loop in sequence, andmeans operating to restore the said element to-its originalpositionafter the loop has been released.

18. In a sewing machine, the combination with a reciprocating needle, ofan angularly movable loop drawing device, operating to draw outsuccessive loops from the needle thread but'allow each loop to bereleased before its bight has been carried through two right angles ofangular movement, and a ten sion device comprising a casing around whichthe-loops pass, a loop arresting and retaining element rotatably mountedwithin said casing, and means for centralizing the loop so as to be inposition for penetration by the needle. v i

1-9. In a sewing machine, the combination with a reciprocating needle,of an angularly movable loop drawing device, operating to draw outsuccessive loops from the needle thread but allow each loop tobereleased be fore its bight has been carried through two right anglesof angular movement, and a tension devicecomprising. a casing aroundwhich the loops pass, a loop arresting and retaining element rotatablymounted within said casing, anda movable horn which accompanies the loopretaining element dur ing part of its travel and centralizes the loop soas to be in position for penetration by the needle.

20. In a sewing machine, the combination with an angularly movable loopdrawing device operating to draw out successive loops from the needlethread but allow each loop to be released before its bight has beencarried through two right angles of angular movement, of a tensiondevice comprising a casing and a loop arrest-ing and retaining elementtherein, said element comprising two relatively movable members one ofwhich shrouds the other when a loop has been arrested.

21. In a sewing machine, the combination with an angularly movable loopdrawing device, operating to draw out successive loops from the needlethreadbut allow each loop to be released before its bight has beencarried through two right angles of angular movement, of a tensiondevice comprising a casing and a loop arresting and retaining element inthe form of two relatively movable members, a loop-arresting finger onone member, a finger-shrouding arm on the other member, meanswhereby theshrouding arm tends always to shroud the finger, and means whereby thesaid finger is exposed at proper intervals to enable it to perform itsloop arresting and its loop releasing functions.

22. In a sewing machine, the combination with an angularly movable loopdrawing de vice, operating to draw out successive loops from the needlethread but allow each loop to be released before its bight hasbeencarried through two right angles of angular movement, of a tensiondevice comprising a casingand a loop arresting and retaining element inthe form of two relatively movable members, a loop-arresting finger onone member, a finger-shrouding arm on the other member, means wherebythe shrouding arm tends always to shroud the finger, means for lockingthe finger carrying mem her in suitable positions and moving the membercarrying the shrouding arm into an unshrouding position, means wherebythe last mentioned means are operated, and

means whereby the locking and unshrouding of the respective members isagain effected'when the loop arresting and retain ing element as a wholehas,by yielding to the pull of the loop, reached a position in which thefinger is close to the needle hole in the needle plate.

23. In a sewing machine, the combination with an angularly movable loopdrawing device, operating to draw out successive loops from the needlethread but allow each loop to be released before its bight has beencarried through two right angles of angular movement, of a tensiondevice comprising a casing and a loop arresting and retaining element inthe form of two relatively movable members, a loop-arresting finger onone member, a fin ger-shrouding arm on the other member, means wherebythe shrouding arm tends always to shroud the finger, a single membercapable, when operated at proper intervals, of locking the finger-carrying member and of moving the member carrying the shrouding arm into itsunshrouding position, and means for operating the said single member.

24. In a sewing machine, the combination with an angularly movable loopdrawing device, of a stationary tension device situated laterally withrespect to one face of the loop-drawing device, the adjacent facescooperating to draw out successive loops from the needle thread. butallow each loop to be released before its bight has been carried throughtwo right angles of angular movement, the said tension device comprisinga casing and a loop arresting and retaining element in the form of tworelatively movable members one of which shrouds the other when a loophas been arrested.

25. In a sewing machine, the combination with an angularly movable loopdrawing device, of a stationary tension device situated laterally withrespect to one face of the loop drawing device, the adjacent facescooperating to draw out successive loops from the needle thread butallow each loop to be released before its bight has been carried throughtwo right angles of angular movement, the said tension device comprisinga casing, a loop arresting and retaining element in the form of tworelatively movable members, a loop arresting finger on one member, afinger shrouding arm on the other member, means whereby the shroudingarm tends always to shroud the finger, and means whereby the said arm ismoved into an unshrouding position to enable the said finger to performits loop arresting and loop releasing functions.

26. In a sewing machine, the combination of an angularly movable disk, astationary tension device located laterally with respect to one face ofsaid disk, a segmental flange on the disk and a groove on the tensiondevice cooperating to engage the needle thread, draw out the bight of aloop between the disk and tension device and release theloop in aposition free to be drawn up around the tension device.

27. Ina sewing machine, the combination of a rotary disk, and astationary casing located laterally with respect to one face of saiddisk, a flange on said disk and a slot in the adjacent face of thecasing cooperating to engage the needle thread, draw out the big'ht of aloop between them, and release the loop in a position free to be drawnup around the casing.

28. In a sewing machine, the combination of a rotary disk, a stationarytension device located laterally with respect to one face of said disk,and means whereby loops of needle thread are engaged, drawn out betweenthe needle loops.

29. Ina sewing machine, the combination of a rotary member and alaterally situated stationary casing each having means on their adjacentlateral faces cooperating with one another to engage the needle thread,draw out a loop, and release it in a position whence it can be drawn uparound the casing.

30. In a sewing machine, the combination of a rotary disk a stationarytension device situated laterally with respect to one face of said disk,the disk and tension device each having means on their adjacent faceswhich cooperate to engage the needle thread, draw out a loop and releasethe same within one hundred and twenty degrees of movementof the disk.

In testimony whereof I my signature in presence 01 two witnesses.

FREDERICK BAKER.

VVitnesses A. H. STEVENS, H. D. JAMEsoN.

Copies of this patent maybe obtained for five cents each, by addressingthe Commissioner of Patents,

Washington, D. C.

